Telephone system.



B. G. JAMIESON.

v TELEPHONE SYSTEM.

I APPLICATION FILED AUG. 15, 1911. v 1,1 1 9,083. Patented Dec. 1,1914.

1 m5 Q; @g k g i m @i g in] RF 1 m g N3 :ifi q I I J I I I I I M Wm i F? MGVW BERTB-AND G. 'JAMInsoN, or CHICAGO, ILLINOIS.

, TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Dec. 1, 1914.

Application filed August 15, 1911. Serial No. 644,175.

To all whom it may concern:

Be it known that I, BERTRAND G. JAMIE- son, a citizen of the United States, residing at Chicago,in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Telephone Systems, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to telephone systems and has for its object theprovision of means whereby certain signaling indications may be established at the central exchange at the will of the subscriber. My invention is of particular utility for private branch exchange switchboards, although not so limited. L

In this description and drawing, I show and describe my invention as applied to a common battery telephone system, although it will be understood it is not tobe solimited. It is customary in'common battery systems, for instance, for a signal to. be operated at the exchange in response to the actuation of the switchhook lever at the sub station. My invention concerns'itself with the provision of means wherebythe operator may receive a further signaling indica tion which notifies the operator that the subscriber is temporarily away from his instrument and which signaling indication may be discontinued when the subscriber returns so that he is again accessible through the instrument. In my application Serial No. Gal-1,174, filed Aug. 15,1911, I set forth asystem having these general characteristics in which an audible signal may be conveyed to the operator when it is desired by her to connect with the line under consideration, and the broad claims covering a system of the general character described therein and herein are inserted in said application.

I11 the form shown herein my invention concerns itself with providing visual signaling means at the exchange whereby the subscriber may selectively actuate his signaling means so as to indicate to the operator that the subscriber is away from the instrument.

I will explain my invention more in detail by reference to the accompanying drawing illustrating one embodiment thereof diagrammatically. I

In the drawing I have illustrated a cenently appear.

tral exchange A and two substations B and C served by this exchange. The substation B has the customary receiver 1, switchhook lever 2, induction coil 3, condenser 4, trans mitter ,5, signal receiving device 6 and condenser 7 all associated with the line wires 8 and 9. The equipment is similar at the substation C. The lines 8 and 9 at the central exchange are associated with the line relay 10, cut off relay 11, common battery 12, an swermg ack 13, answerlng lamp 14 and multiple jacks 15. The thimbles 16 of the jacks are connected together by means of the conductor 17 as is well understood and this conductor is associated with a cut off relay 11, the other terminal of said cut off relay being grounded. Th1s lme circuit arrangement and also the cord circuit arrangeclose the line circuit at the substation, the answering lamp 114 is actuated by the line relay 10 to be extinguished thereafter by the cut off relay 11. At the substation I further provide a switch consisting of a spring 27 ,-a contact 28, resistance 29 and button 30 which I utilize for sending a selective signal to the central station to apprise the-operator when attempting to connect with this line, that said line is not available as the subscriber is temporarily away from his instrument. When the relay 10 receives its full energizing current as when the switchhook lever-'2 is in its raised position, then the armatures 31 and 32 are attracted to light the lamp 1 1 and also to perform another function that will pres- Should however a less amount of current be supplied to the relay 10 as when the button 30 is actuated to close the circuit across the conductors 8 and 9 through the resistance 29, then this current is not suflicient to actuate the armature 32, but sufficient to actuate the armature 31, which armature 31 therefore is in close circuit with its contact 33, and by means of the 35 supplies the lamp 14: with only sufficient current to light it very dimly. It will thus be seen that while the button 30 is depressed the lamp 1-1 glows and the operator upon trying to connect with that line is apprised of the fact that the subscriber of that particular line is temporarily away from the instrument so that she can notify the calling party of such condition and save the time necessary to make a fruitless call for the said substation. The resistance 29 ispreferably of high inductive qualities so that it does not influence talking conditions should the operator wish to call the corresponding substation, even though the associated lamp 14;. signifies that the subscriber is not there or does not wish to be called as such occasion might arise in an emergency. An arm 36 is provided associated with the switchhook lever 2 so that should a call be initiated from substation B without restoring the button 30, this restoration is automatically accomplished by the removal of the receiver from the switchhook. At substation C it will thus be seen that not only the answering but the multiple jacks are provided with means whereby the subscriber may establish distinctive conditions so that the operator will be apprised of the availability of the line when she desires to, make a call. A great deal of time can thus be saved. The push button 30 may also be under direct control of some other instrumentality that actuates manually, and this is illustrated at substation C where the push button 30 is under the control of the sliding top 87 of a roll desk, the table top of which is indicated at 38.

In the claims I use the expression means at the exchange for establishing the busy and not busy condition of the associated circuit, and in the specific form herein shown these means would be the jack thimbles 16.

As before stated I am showing the invention specifically here in connection with a common battery system and also describe specifically merely one embodiment of the many which my invention may take. I do not limit myself therefore to this specific description, but

Having thus described one embodiment of my invention, what I claim as new and desire to secure by Letters Patent is:

1. A telephone system having a central exchange, a plurality of substations, and circuits uniting said substations with said central exchange, means at the exchange for establishing the busy and notlbusy condition of the associated circuit, cord circuits for said exchange, a line lamp for each substation adapted to be illuminated only when its associated circuit is not connected with a cord circuit, means at the substation for causing the bright illumination of said lamp, and means controlled at the substation for causing a dim illumination of said lamp.

2. A telephone system having a central exchange, a plurality of substations, and

circuits unitingsaid substations with said exchange, a plurality of substations,- circuits uniting said substations with said central exchange, cord circuits at, said exchange, means at the exchange for establishing a busy and not busy condition of the associated circuit, visual signaling means at the exchange corresponding to each substation operable only when the associated circuit is unconnected with a cord circuit, means at the substation for causing the actuation of said visual signaling means to indicate the desire for a call, and means controlled at the substation for causing the actuation of said visual signaling means in a different manner than when requesting a call.

In witness whereof, I'hereunto subscribe =my name this 3rd day of August A. D., 1911.

BERTRAND G. J AMIESON.

Witnesses:

HAZEL Jones, MAX W. ZABEL.

Copies of this patent may be obtained for five cents each, by addressing the Gommissioner'of Patents,

Washington, D. 0. 

